/*********************************************************************************
This code is provided for internal research and development purposes by Huawei solely,
in accordance with the terms and conditions of the research collaboration agreement of May 7, 2020.
Any further use for commercial purposes is subject to a written agreement.
 *  OKVIS - Open Keyframe-based Visual-Inertial SLAM
 *  Copyright (c) 2015, Autonomous Systems Lab / ETH Zurich
 *  Copyright (c) 2016, ETH Zurich, Wyss Zurich, Zurich Eye
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions are met:
 * 
 *   * Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright notice,
 *     this list of conditions and the following disclaimer in the documentation
 *     and/or other materials provided with the distribution.
 *   * Neither the name of Autonomous Systems Lab / ETH Zurich nor the names of
 *     its contributors may be used to endorse or promote products derived from
 *     this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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 *
 *  Created on: Aug 30, 2013
 *      Author: Stefan Leutenegger (s.leutenegger@imperial.ac.uk)
 *    Modified: Zurich Eye
 *********************************************************************************/

/**
 * @file PoseParameterBlock.hpp
 * @brief Header file for the PoseParameterBlock class.
 * @author Stefan Leutenegger
 */

#pragma once

#pragma diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
// Eigen 3.2.7 uses std::binder1st and std::binder2nd which are deprecated since c++11
// Fix is in 3.3 devel (http://eigen.tuxfamily.org/bz/show_bug.cgi?id=872).
#include <Eigen/Core>
#pragma diagnostic pop

#include <ze/common/transformation.hpp>
#include <ze/nlls/parameter_block.hpp>
#include <ze/nlls/pose_local_parameterization.hpp>

namespace ze {
namespace nlls{

/// \brief Wraps the parameter block for a pose estimate
class PoseParameterBlock : public ParameterBlock
{
public:
  EIGEN_MAKE_ALIGNED_OPERATOR_NEW

  typedef Transformation estimate_t;

  static constexpr size_t c_dimension = 7;
  static constexpr size_t c_minimal_dimension = 6;

  /// \brief Default constructor (assumes not fixed).
  PoseParameterBlock();

  /// \brief Constructor with estimate and time.
  /// @param[in] T_WS The pose estimate as T_WS.
  /// @param[in] id The (unique) ID of this block.
  /// @param[in] timestamp The timestamp of this state.
  PoseParameterBlock(const Transformation& T_WS, uint64_t id,
                     const int64_t& timestamp);

  virtual ~PoseParameterBlock();

  // ---------------------------------------------------------------------------
  // Setters.

  virtual void setEstimate(const Transformation& T_WS);

  void setTimestamp(const int64_t timestamp) { timestamp_ = timestamp; }

  // ---------------------------------------------------------------------------
  // Getters

  Transformation estimate() const;

  int64_t timestamp() const { return timestamp_; }

  virtual double* parameters() { return parameters_; }

  virtual const double* parameters() const { return parameters_; }

  virtual size_t dimension() const { return c_dimension; }

  virtual size_t minimalDimension() const { return c_minimal_dimension; }

  // minimal internal parameterization
  // x0_plus_Delta=Delta_Chi[+]x0
  /// \brief Generalization of the addition operation,
  ///        x_plus_delta = Plus(x, delta)
  ///        with the condition that Plus(x, 0) = x.
  /// @param[in] x0 Variable.
  /// @param[in] Delta_Chi Perturbation.
  /// @param[out] x0_plus_Delta Perturbed x.
  virtual void plus(const double* x0, const double* Delta_Chi, double* x0_plus_Delta) const
  {
    PoseLocalParameterization::plus(x0, Delta_Chi, x0_plus_Delta);
  }

  /// \brief The jacobian of Plus(x, delta) w.r.t delta at delta = 0.
  /// @param[in] x0 Variable.
  /// @param[out] jacobian The Jacobian.
  virtual void plusJacobian(const double* x0, double* jacobian) const
  {
    PoseLocalParameterization::plusJacobian(x0, jacobian);
  }

  // Delta_Chi=x0_plus_Delta[-]x0
  /// \brief Computes the minimal difference between a variable x and a perturbed variable x_plus_delta
  /// @param[in] x0 Variable.
  /// @param[in] x0_plus_Delta Perturbed variable.
  /// @param[out] Delta_Chi Minimal difference.
  /// \return True on success.
  virtual void minus(const double* x0, const double* x0_plus_Delta, double* Delta_Chi) const
  {
    PoseLocalParameterization::minus(x0, x0_plus_Delta, Delta_Chi);
  }

  /// \brief Computes the Jacobian from minimal space to naively overparameterised space as used by ceres.
  /// @param[in] x0 Variable.
  /// @param[out] jacobian the Jacobian (dimension minDim x dim).
  /// \return True on success.
  virtual void liftJacobian(const double* x0, double* jacobian) const
  {
    PoseLocalParameterization::liftJacobian(x0,jacobian);
  }

  /// @brief Return parameter block type as string
  virtual std::string typeInfo() const
  {
    return "PoseParameterBlock";
  }

private:
  double parameters_[c_dimension];
  int64_t timestamp_; ///< Time of this state.
};

} // namespace nlls
} // namespace ze
